Storing and interlocking typewriter input mechanism

ABSTRACT

Keys of a typewriter actuate control levers which cooperate with first locking means so that only one key can be actuated at a time. The control levers actuate control bars which cooperate with second locking means so that only one control bar at a time can move to an operative position for actuating typing means. Another control bar, actuated before completion of the operation of the typing means, is held by the second locking means in an intermediate position in which the corresponding control lever is still in the first locking means, preventing actuation, until the respective control bar can be moved by a spring from the intermediate position to the operative position due to return movement of the first actuated control bar out of the operative position.

I 1March 20, 1973 STORING AND INTERLOCKING TYPEWRITER INPUT MECHANISM [75] Inventors: Chien Van Der Wei-f, Carolinensiel;

Roll Theilen, Sande, both of Germany [73] Assignee: Olympia Werke AG, Wilhelms'haven, Germany 22 Filed: June 18,1971

21 Appl.No.: 154,404

[30] Foreign Application Priority Data July 11, 1970 Germany ..P 20 34 583.9

[52] US. Cl. ..l97/l07, 197/16, 197/98 [51] Int. Cl. ..B4lj 5/22 [58] Field of Search....197/16, 17, 98, 107, 108, 109, 197/110, 111,112

[56] References Cited UNITED STATES PATENTS 606,944 7/1898 Sears ..l97/l07 2,236,413 3/1941 Pirnat et a1. 197/107 3,086,635 4/1963 3,152,759 10/1964 3,191,740 6/1965 3,353,646 ll/l967 Primary Examiner-Emest T. Wright, Jr. Attorney-Michael S. Striker [5 7 ABSTRACT Keys of a typewriter actuate control levers which cooperate with first locking means so that only one key can be actuated at a time. The control levers actuate control bars which cooperate with second locking means so that only one control bar at a time can move to an operative position for actuating typing means. Another control bar, actuated before completion of the operation of the typing means, is held by the second locking means in an intermediate position in which the corresponding control lever is still in the first locking means, preventing actuation, until the respective control bar can be moved by a spring from the intermediate position to the operative position due to return movement of the first actuated control bar out of the operative position.

10 Claims, 5 Drawing Figures STORING AND INTERLOCKING TYPEWRITER INPUT MECHANISM BACKGROUND OF THE INVENTION The present invention relates to a typewriter input mechanism in which a simultaneous actuation of several keys is prevented. For obtaining a high average typing speed, it is necessary that unrhythmical sequences of key actuations are mechanically stored and the respective operations automatically carried out after release of the respective keys so that no delays occur in the sequence of character printing operations.

The U. 8. Pat. No. 3,086,635 discloses an arrangement in which intermediate levers of an electric typewriter, cooperate with roller locking-means which only released after a longitudinal movement of the intermediate lever has started, so that a second key actuation is substantially delayed. If the second key actuation occurs too early, the intermediate lever cannot engage the locking means, and the manual key operation encounters an unexpected and undesirable resistance. Only when the locking means is again free, can the intermediate lever engage, and the operation of the intermediate lever is then stored during the time remaining of the machine operation caused by a previously actuated key. It is not a true storing, but only a storing for a short time, which can only become effective when the locking means is released.

The German patent P 19 27 963 discloses an arrangement in which the intermediate member of the type lever action can be released by an impulse movement of a key lever, whereupon the intermediate member automatically engages a locking means, automatically effects printing operation in a sequence, and can be returned by power means to a position of rest. Printing due to simultaneous actuation of two keys is prevented, but two intermediate members are located in a stored position, which have to be returned if the writing operation is to be continued. A disentanglement bar is required which is operated by a special key, so that the typing rhythm is substantially disturbed.

SUMMARY OF THE INVENTION It is one object of the invention to provide an interlocking and storing typewriter input mechanism which overcomes the disadvantages of the prior art.

Another object of the invention is to provide a typewriter input mechanism which assures a printing of successive types in the correct sequence, while the second of two directly successive key impulses, is automatically mechanically stored until the first started operation has been completed.

Another object of the invention is to provide a typewriter input mechanism in which manual key impulses following each other in an irregular sequence are transformed to type actuations in a uniform sequence, without requiring a disentanglement bar.

With these objects in view, the present invention provides in addition to a first locking means, a second locking means which operates at a phase shift to the first locking means. The second locking means cooperates with control bars, and permits only one control bar to move to an operative position while the next-following control bar is held in an intermediate position until the locking means is free and the second control bar can automatically move to the operative 0 channel, permitting only one first control means at a time to move to the actuated position; a set of second control means, preferably control bars, controlled by the first control means, respectively, each second control means having a normal position arrested by arresting means, and an operative position, and being biased by a spring to move to the operative position, each second control means in the arrested normal position being released by the respective first control means moving to the actuated position, and starting movement towards the operative position; typing means actuated by each second control means in the operative position to type different characters in accordance with coded projections on the second control means cooperating with switches; second locking means, preferably also including a ball locking channel, permitting only one of the second control means at a time to move to the operative position, and holding another subsequently released second control means in an intermediate stored position, the second control means in the intermediate stored position holding the respective associated first control means in the actuated position so that all remaining first control means are locked in the position of rest, and lock the respective keys; and

power return means actuated by each second control means moved out of the normal arrested position to cause movement of the respective second control means after actuation of the typing means back to the arrested normal position so that the second locking means permits the other second control means to move from the intermediate stored position to the operative position.

In a preferred embodiment of the invention, the first and second control means have interengaging portions so that the movement of a second control means to the operative position is transmitted to the respective first control means which is engaged by the first locking means, for moving the same out of engagement with the first locking means.

This arrangement substantially reduces the time interval between two directly successive key actuations, since the first control means is unlocked by a spring force released directly upon actuation of a key.

The novel features of the invention which are considered as characteristic for the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a fragmentary schematic side view of a mechanism according to the invention, and including a schematic perspective view of typing means;

FIG. 1a is a fragmentary front view, partially broken off, and illustrating a clutch used in the embodiment of FIG. 1;

FIG. 2 is a fragmentary side view, partially in section, illustrating the mechanism of FIG. 1 in a second operational position;

FIG. 3 is a fragmentary schematic side view illustrating the mechanism of FIG. 1 in a third operational position; and

FIG. 4 is a sectional view illustrating locking means used in the embodiment of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawing, key levers 1 are mounted on a shaft 44a carried by a stationary support 44 for angular movement between a normal position of rest abutting a stop lb due to the action of springs 66 and a depressed position abutting a stop 1c. Each key lever 1 has a projection 1a which cooperates, respectively, with control levers 5 having slots 4 in which a shaft 3 is located so that all control levers 5 are turnable about shaft 3, but also movable in a translatory movement with slot 4 being displaced relative to shaft 3. A spring 7 connects each control lever 5 with a correlated key lever 1, and urges the respective control lever 5 to the illustrated normal position of rest. Spring 7 is slanted to the direction of the slot 4, and consequently biases control lever 5 to turn in counterclockwise direction, and also move to a position in which the shaft 3 is located at the left end of slot 4, as viewed in the drawing.

Each control lever 5 has a plate portion 9, also shown in FIG. 4, which cooperates with a first locking means 11. As best seen in FIG. 4, locking means 11 has a channel 11a closed at the ends by end members 11b, and the slots 11c through which the plate 9 of the control levers 5 can enter channel 11a. A pair of springs 69 and 71 is provided at the ends of channel 1 la, which is filled with a row of rollers 67 which, in a known manner, permit the entry of only one plate 9 of a single control lever 5 between two adjacent rollers 67 When a key lever 1 is depressed, its blade 9 enters channel 11a, and spreads the rollers 67, so that no other plate 9 of another control lever 5 can enter the channel 11a, whereby after actuation of a key lever 1, no second key lever 1 can be operated. This blocking of the control levers 5, and thereby of the key levers 1, takes place as soon as the end of plate 9 is located at the center of the locking channel 11a.

The depression of any key lever 1 causes turning of control lever 5 about shaft 3 while plate 9 enters the locking means 11. A control bar 15 is located under each control lever 5, cooperating with the same. Each control bar 15 is biased by a slanted spring 17 to a normal position in which an arresting portion 19 thereof engages an arresting abutment 21. Spring 17 not only biases the respective control bar 15 to turn in clockwise direction until abutting by a guide face 59 a stop 61, but also biases control bar 15 in longitudinal direction toward the left. In the normal position of control bar 15, illustrated in FIG. 1, a locking plate 41 of control bar 15 is located in a cavity 46 of stationary support 44 which has a second locking means 43 constructed in the same manner as the first locking means 11 illustrated in FIG. 4.

When a key lever 1 is depressed and turns the respective control lever 5, the abutment 13 presses the end of control bar 15 downward, while plate 9 enters between two adjacent rollers 67. Control bar 15 turns in clockwise direction out of the arrested normal position shown in FIG. 1, so that arresting portion 19 releases arresting stop 21.

The longitudinal pull of spring 17 immediately displaces control bar 15 to the left to the operative position shown in FIG. 2 in which the locking plate 41 enters between two adjacent locking rollers 67 of the second locking means 43 so that no other locking bar 15 can be displaced in a translatory movement ,by spring 17.

During the movement of the operated control bar 15 to the operative position of FIG. 2, the locking plate 9 of the respective control lever 5 is moved out of the locking means 11, moving in a horizontal direction due to the interengagement between the portion 39 of control lever S, and the portion 37 of control bar 15.

Due to this function of control bar 15, the control lever 5, which immediately blocks all key levers 1, except the actuated key lever 1, is quickly released so that the next key lever 1 can be operatednT'he second operated key lever 1, moves its locking plate 9 into the locking means 11, and turns the correlated control bar 15 to a position in which arresting portion 19 releases arresting stop 21, as shown in FIG. 3. However, since a locking plate 41 is already located in locking means 43, the locking plate 41 of the second actuated control bar 15 cannot enter the locking means 43, as shown in FIG. 3.

The camming portion 59 of control bar 15 is guided by stationary stop 61 so that a coupling portion 63 is located in the path of movement of a coupling portion 65 of an angularly reciprocating return member 35, by which the control bar 15 is pushed back from its operative position, in which locking plate 41 is located in locking means 43, first in longitudinal translatory movement to a position in which arresting portion 19 is located adjacent stop 21, whereupon the slanted spring 17 pulls control bar 15 to the arrested normal position shown in FIG. 1.

A universal bail 23 extends across all control bars 15 and is pivotally mounted at 23a. The bail 23 cooperates with the arm a of a lever 75 which is mounted on a shaft 76 for angular movement. Lever 75 is connected by a wire link 77 with an angular releasing lever 78 turnably mounted on a shaft 79. Releasing lever 78 has a normal position in which it is held by spring 80 on a stationary stop 81. One arm of releasing lever 78 has an abutment 82 cooperating with two stops 83 and 84 diametrically disposed on a gear 27 which is connected with one end 85 of a coil spring 86 wound on a shaft 25, as best seen in FIG. 1a.

When gear 27 is stopped by the abutment 82 of lever 78 engaging one of the stops 83, 84, the spring 86 is loosened so that gear 22 is disengaged from the drive shaft 25. On the other hand, when the abutment 82 releases the stop 83 or 84, the spring 86 contracts, and couples gear 27 to the rotating drive shaft 25.

Gear 27 meshes with the gear 29 which has an eccentric pivot 31 connected with a link 33 which reciprocates during rotation of gear 29 and eccentric pivot 31 to angularly reciprocate the return member 35 with its coupling portion 65 which cooperates with the abutments 63 of all control bars 15.

When after key actuation a control lever 5 displaces the correlated control bar 15, bail 23 is operated in counterclockwise direction so that lever 75 also turns in counterclockwise direction, whereby the link 77 turns the release lever 78 in counterclockwise direction. Abutment 82 of lever 78 moves out of the path of stop 83 of gear 27, so that the coil spring 86 can contract whereby gear 27 is coupled with the rotating drive shaft 25. By means of the transmission 27, 29 and link 33, reciprocating return member 35 is angularly turned and its coupling portion 65 engages coupling portion 63 of the operative control bar to return the same to the normal arrested position. In the meantime, release lever 78 has been returned by spring 80 to its normal position abutting stop 81. After half revolution of gear 27, the other stop 83 on gear 27 abuts the abutment 82 of lever 78, so that the clutch 25, 86, 27 is again disengaged. The ratio between the gear 27 and the gear 29 is 2 1, which means that after half a revolution of gear 27 gear 29 has completed a full revolution. Release lever 78 is returned by spring 80 to its normal position, and returns through link 77, angular lever 75, and bail 23 to the normal position.

Each of the control bars 15 has projections 51 arranged in accordance with a code for representing different characters. For example, the foremost control bar 15 in FIG. 1 has two integral code projections 51. The code projections 51 cooperate with actuators 55, turnable about pivots 53. Each actuator 55 cooperates with a switch 57, connected to the electric setting device 49 of a typehead 45 which cooperates with the platen 47, as schematically shown in FIG. 1. In accordance with the selected switches 57 operated by the code projections 51 of a selected control bar 15, the typehead 45 is angularly displaced about two intersecting or crossing axes to select a type on the typehead 45. As it is well known to those skilled in the art, the types are arranged in circular rows and columns, and the setting means 49 moves with typehead 45 along rails 49a extending parallel to platen 47.

Only when a control bar 15 in the operative position has operated the respective switches 57, is the displacement of the bail 23 by the respective control bar 15 effective to cause an operation of the return member 35. Key levers 1, and control levers 5 are returned to normal positions of rest by springs 66 and 7, irrespective of the power return means 25, 86, 27, 29, 33, and 35.

Due to the provision of two locking means 1 l and 43, it is not only prevented that two key levers 1 can be simultaneously actuated, but it is also possible to store an impulse representing actuation of the next following key until the first started operation has been completed.

The control levers 5 have projecting noses 73 under the abutments 39, which cooperate with control edges 37 of control bars 15 in such a manner that control bars 15 cannot be accidentally disconnected from the associated control levers 5.

OPERATION When a key lever 1 is depressed, its projection 1a engages the correlated control lever 5 and turns the same about shaft 3 in clockwise direction away from stop 5a, and against the action of spring 7. At the same time, locking plate 9 enters between two adjacent rollers 67 of locking means 11. Due to the fact that locking means 11 is provided with the end springs 69 and 71, entering of any locking plate 9 between two locking rollers 67 requires the same force, and the same number of rollers 67 is always displaced, irrespective of whether the locking plate 9 enters between locking rollers 67 at the end of the locking channel 11a, or at the center of the same.

Due to the downward displacement of the portion 37 of control bar 15 by the abutment 13 of the control lever 3, the arresting portion 19 is moved downward away from the arresting stop 21, and the arresting means 19, 21 are released, so that spring 17, which had urged control bar 15 to the arrested normal position, is now effective in longitudinal direction of control bar 15, to move the same in a translatory movement to the left as viewed in the drawing to the operative position shown in FIG. 2. The camming portion 59 is guided by the guide stop 61 so that the coupling projection 63 of control bar 15 is located directly adjacent coupling projection 65 of reciprocating return member 35 and in the path of the coupling projection 65.

The locking portion 41 of the control bar 15 in the operative position of FIG. 2, is located between locking rollers 67 of the locking means 43, which is constructed in the same manner as the locking means 11, shown in FIG. 4. When the operated control bar 15 is in this operative position, no other control bar 15 can move to the operative position, since it is blocked by the locking means 43.

. The control bar 15 in the operative position actuates by means of the code projections 51 corresponding actuators 55 which close the respective switches 57 in accordance with the coded information of the code projections 51, and effect setting of the typehead 45 to a position in which the type representing the same character as the originally operated key lever 1, is located opposite the printing area of platen 47 so that a corresponding print can be made in the usual manner.

The displacement of control bar 15 to the operative position operates bail 23 so that through the linkage means 75, 77, 78 the abutment 82 is moved out of engagement with the stop 83 on gear 27 so that the coil spring 86 contracts and clutches gear 27 to the rotating drive shaft 25 causing operation of the reciprocating return means 35 through transmission 27, 29 and linkage 31, 33. Coupling projection 65 engages coupling projection 63 of control bar 15 in the operative position and pushes the same back to the normal position against the action of spring 17 until the relative position of arresting portion 19 and arresting stop 21 permit spring 17 to turn control bar 15 to the normal arrested position in which arresting portion 19 engages arresting stop 21, as shown in FIG. 1.

Since the translatory movement of control bar 15 due to the action of spring 17 upon release of the arresting means 19, 21 causes also a translatory movement of the respective control lever 5, locking plate 9 of control lever 5 is moved in horizontal direction out of the locking means 11, as shown in FIG. 2. The relative movement between control lever 5 and control bar 15 is made possible by the slot 4 and shaft 3 in the same.

When locking plate 9 was still engaged by the locking means 11, due to actuation of a first key lever 1, no other control lever 5 could be operated since all other key levers 1 are locked by the respective correlated control levers 5 blocked from entering the locking means 11. However, this key lock is only momentary, and is immediately released when locking plate 9 of the first actuated control lever 5 moves out of the locking means 11 due to the translatory movement of control bar 15 by spring 17. Consequently, it is almost immediately possible to depress a second control lever 5 associated with another character, and this information is stored in accordance with the invention. The second actuated key lever 1 turns the correlated second control lever 5, whose locking plate 9 enters locking means 11, and which at the same time turns the second control bar l5to a released position in which arresting portion 19 is no longer arrested by arresting stop 21, as shown in FIG, 3. However, since the locking plate 41 of the first operated control bar 15 is located in the locking means 43, the locking plate 41 of the second operated control bar 15, shown in solid lines in FIG. 3, cannot fully enter into the blocked locking means 43, and consequently the second actuated control bar 15 remains momentarily in the position of FIG. 3, storing the information that a second key associated with another character has been actuated. Locking plate 9 of the second actuated control lever 5 is located in locking means 11, so that no other control lever 5 can be displaced by a third actuated key lever 1, so that the keyboard is locked.

Only when the reciprocating return means 35 returns the first actuated control bar 15 to a position in which spring 17 is effective to turn the returned control bar 15 until arresting shoulder 19 engages arresting stop 21, spring 17 of the second actuated control bar 15 moves the same from the intermediate position shown in FIG. 3 in solid lines to the operative position shown in chain lines in FIG. 3, so that the typing means 49, 45, 47, 57, 55 are operated.

The second control bar 15 moving to the operative position shifts the respective correlated control lever 5 to the position shown in F IG. 9 so that its locking plate 9 is released by locking means 1 l, and a third key lever 1 can be operated while the second operated control bar 15, now in the operative position, effects printing of its correlated character.

It will be seen that the operation of the two locking means 11 and 43 is phase displaced so that the control bar 15 in the intermediate stored position is already released by arresting means 19, 21, while the respective associated control lever 5 still engages the first locking means 1 1. Due to the latter fact, a third key lever 1 cannot be operated, so that at all times, only one control bar 15 can be in the operative position, and one control bar 15 can be in stored intermediate position, so that the mechanism does not need a disentanglement bar.

It is evident that different typing means, including type actions and type bars could be used instead of the typehead 45.

It will be understood that each of the elements described above, or two or more together, may also find a useful application in other types of typewriter input mechanisms differing from the types described above.

While the invention has been illustrated and described as embodied in a storing and interlocking typewriter keyboard mechanism including first and second control means for the typing means, and first and second locking means for the first and second control means, respectively, it is not intended to be limited to the details shown since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and, therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims.

We claim:

1. Storing and interlocking typewriter input mechanism, comprising a set of key means; a set of first control means spring biassed to a position of rest, and being operable by said key means, respectively, to move to an actuated position; first locking means permitting only one first control means at a time to move to said actuated position, and engaging the one first control means which is in said actuated position; arresting means; a set of second control means controlled by said first control means, respectively, each second control means having a normal position arrested by said arresting means and an operative position, and being spring biassed to move to said operative position, each second control means in said arrested normal position being released by the correlated first control means moving to said actuated position to move to said operative position; typing means actuated by each second control means in said operative position to type a different character; second locking means permitting only one of said second control means at a time to move to said operative position, and holding an other subsequently released second control means in an intermediate stored position, said second control means in said intermediate stored position holding the respective associated first control means in said actuated position so that all remaining first control means are locked in said position of rest, and lock the respective key means; and power return means actuated by each second control means moved out of said normal arrested position to cause movement of the respective second control means after actuation of said typing means back to said arrested normal position so that said second locking means permits the other second control means to move from said intermediate stored position to said operative position.

2. Mechanism as claimed in claim 1 wherein said first control means and said second control means have interengaging portions so that the movement of a second control means to the operative position is transmitted to the respective first control means which is engaged by said first locking means for moving said first control means out of engagement with said first locking means.

3. Mechanism as claimed in claim 2 comprising a stationary support shaft; and wherein each of said first control means has a slot through .which said shaft passes so that said first control means are mounted for turning and translatory movement; wherein said key means cause turning movement of said first control means from said position of rest to said actuated position engaged by said first locking means; and wherein movement of said second control means to said operative position causes translatory movement of said first control means out of engagement with said first locking means.

4. Mechanism as claimed in claim 1 wherein each control means of said first and second control means has a blocking plate; wherein each locking means of said first and second locking means includes a channel having closed ends, a row of rolls in said channel, spring means between said closed ends and the outermost rolls of said row; and wherein one of said blocking plates of said first and second control means, respectively, is located between two adjacent rolls of said row in said actuated and operative positions, respectively.

5. Mechanism as claimed in claim 1, wherein said first control means include control levers and first springs connected with said control levers for biassing said control levers toward said position of rest; and wherein said second control means include control bars and second springs connected with said control bars for biassing said control bars toward said intermediate stored position and said operative position.

6. Mechanism as claimed in claim 5 wherein said control bars are mounted for translatory and angular movement; wherein said control bars are turned by said control levers, respectively, out of said normal arrested position and are then moved by said second springs in a translatory movement toward said intermediate and operative positions; and wherein said power return means move said control bars in a translatory movement toward said normal position until said second springs turn said control bars to said normal arrested position.

7. Mechanism as claimed in claim 1 wherein said power return means includes a universal bail crossing said second control means and being displaced by any one of said second control means moved out of said normal arresting position by the respective first control means; a drive shaft; an automatic clutch having one part driven by said shaft, and an other part; a linkage connecting said bail with said clutch so that displacement of said bail by one of said second control means causes movement of said clutch to an engaged position in which said parts are connected; a reciprocating means cooperating with said second control means; and a transmission connecting said other part with said reciprocating means so that said transmission and said reciprocating means are operated in said engaged position of said clutch to return said second control means from said operative position to said arrested normal position whereupon said clutch automatically disengages after turning of said other part through a predetermined angle.

8. Mechanism as claimed in claim 1 wherein said first control means are mounted for angular movement between said position of rest and said actuated position, and for translatory movement out of engagement with said first locking means; and wherein said second control means are mounted for angular movement out of said arrested normal position to a released position, and for translatory movement from said released position to said intermediate stored position and said operative osition.

9. Mec amsm as claimed in claim 1 wherein each second control means has projections arranged in accordance with a code for representing different characters; wherein said typing means are electrically operated and comprise a series of switch means, and a series of movable actuators for operating said switch means, respectively; wherein said projections of a selected second control means moving to said operative position displace corresponding selected actuators for operating the corresponding switches means, whereby characters are typed selected in accordance with the arrangement of said projections.

10. Mechanism as claimed in claim 1 wherein each second control means includes a control bar mounted for angular movement by the respective first control means out of said normal arrested position to a released position, and back, and for longitudinal movement between said released position and said operative position, and back, and a spring slanted to said control bar and connected with said control bar for biassing said control bar in said released position to move to said operative position, and for biassing said control bar to turn from said released position to said arrested normal position when said control bar is returned by said return means from said operative position to said released position. 

1. Storing and interlocking typewriter input mechanism, comprising a set of key means; a set of first control means spring biassed to a position of rest, and being operable by said key means, respectively, to move to an actuated position; first locking means permitting only one first control means at a time to move to said actuated position, and engaging the one first control means which is in said actuated position; arresting means; a set of second control means controlled by said first control means, respectively, each second control means having a normal position arrested by said arresting means and an operative position, and being spring biassed to move to said operative position, each second control means in said arrested normal position being released by the correlated first control means moving to said actuated position to move to said operative position; typing means actuated by each second control means in said operative position to type a different character; second locking means permitting only one of said second control means at a time to move to said operative position, and holding an other subsequently released second control means in an intermediate stored position, said second control means in said intermediate stored position holding the respective associated first control means in said actuated position so that all remaining first control means are locked in said position of rest, and lock the respective key means; and power return means actuated by each second control means moved out of said normal arrested position to cause movement of the respective second control means after actuation of said typing means back to said arrested normal position so that said second locking means permits the other second control means to move from said intermediate stored position to said operative position.
 2. Mechanism as claimed in claim 1 wherein said first control means and said second control means have interengaging portions so that the movement of a second control means to the operative position is transmitted to the respective first control means which is engaged by said first locking means for moving said first control means out of engagement with said first locking means.
 3. Mechanism as claimed in claim 2 comprising a stationary support shaft; and wherein each of said first control means has a slot through which said shaft passes so that said first control means are mounted for turning and translatory movement; wherein said key means cause turning movement of said first control means from said position of rest to said actuated position engaged by said first locking means; and wherein movement of said second control means to said operative position causes translatory movement of said first control means out of engagement with said first locking means.
 4. Mechanism as claimed in claim 1 wherein each control means of said first and second control means has a blocking plate; wherein each locking means of said first and second locking means includes a channel having closed ends, a row of rolls in said channel, spring means between said closed ends and the outermost rolls of said row; and wherein one of said blocking plates of said first and second control means, respectively, is located between two adjacent rolls of said row in said actuated and operative positions, respectively.
 5. Mechanism as claimed in claim 1, wherein said first control means include control levers and first springs connected with said control levers for biassing said control levers toward said position of rest; and wherein said second control means include control bars and second springs connected with said control bars for biassing said control bars toward said intermediate stored position and said operative position.
 6. Mechanism as claimed in claim 5 wherein said control bars are mounted for translatory and angular movement; wherein said control bars are turned by said control levers, respectively, out of said normal arrested position and are then moved by said second springs in a translatory movement toward said intermediate and operative positions; and wherein said power return means move said control bars in a translatory movement toward said normal position until said second springs turn said control bars to said normal arrested position.
 7. Mechanism as claimed in claim 1 wherein said power return means includes a universal bail crossing said second control means and being displaced by any one of said second control means moved out of said normal arresting position by the respective first control means; a drive shaft; an automatic clutch having one part driven by said shaft, and an other part; a linkage connecting said bail with said clutch so that displacement of said bail by one of said second control means causes movement of said clutch to an engaged position in which said parts are connected; a reciprocating means cooperating with said second control means; and a transmission connecting said other part with said reciprocating means so that said transmission and said reciprocating means are operated in said engaged position of said clutch to return said second control means from said operative position to said arrested normal position whereupon said clutch automatically disengages after turning of said other part through a predetermined angle.
 8. Mechanism as claimed in claim 1 wherein said first control means are mounted for angular movement between said position of rest and said actuated position, and for translatory movement out of engagement with said first locking means; and wherein said second control means are mounted for angular movement out of said arrested normal position to a released position, and for translatory movement from said released position to said intermediate stored position and said operative position.
 9. Mechanism as claimed in claim 1 wherein each second control means has projections arranged in accordance with a code for representing different characters; wherein said typing means are electrically operated and comprise a series of switch means, and a series of movable actuators for operating said switch means, respectively; wherein said projections of a selected second control means moving to said operative position displace corresponding selected actUators for operating the corresponding switches means, whereby characters are typed selected in accordance with the arrangement of said projections.
 10. Mechanism as claimed in claim 1 wherein each second control means includes a control bar mounted for angular movement by the respective first control means out of said normal arrested position to a released position, and back, and for longitudinal movement between said released position and said operative position, and back, and a spring slanted to said control bar and connected with said control bar for biassing said control bar in said released position to move to said operative position, and for biassing said control bar to turn from said released position to said arrested normal position when said control bar is returned by said return means from said operative position to said released position. 